package com.es.stack;

/**
 * 栈的基类
 * @author 二十
 */
public abstract class AbstractStack<E> {

    public abstract void push(E e);

    public abstract E pop();

    public abstract E peek();

    public abstract int getSize();

    public abstract boolean isEmpty();

    @Override
    public String toString() {
        return super.toString();
    }
}
